An essential part of numerical modeling is validating
simulation codes with laboratory experiments that capture
many of the physical processes of interest. Validation is
difficult in astrophysics because the problems of interest
typically encompass complex physics and involve conditions
that are difficult to reproduce in a terrestrial laboratory.
Laboratory astrophysics with intense lasers serves as an
invaluable validation tool by providing the chance to
experimentally probe environments similar to those in which
complex astrophysical phenomena occur. We describe the
process of validating FLASH, an adaptive mesh astrophysical
simulation code for compressible, reactive flows. We present
the results of validation simulations, principally
simulations of laser experiments involving shock propagation
through multi-layer targets performed at the Omega laser
facility at the University of Rochester.

This work was supported by the DOE ASCI/Alliances program at
the University of Chicago under grant No. B341495.